The use of arthroscopy does not increase the incidence of complications in the management of Schatzker IV-VI tibial plateau fractures

BACKGROUND AND OBJECTIVE

The use of arthroscopy for tibial plateau fractures type I, II and III according to Schatzker classification has increased, yet its employment for tibial plateau fractures Schatzker IV, V and VI is controversial due to the potential risk of compartment syndrome, deep vein thrombosis and infection. We aimed to compare the rate of operative and postoperative complications among patients with these types of tibial plateau fractures treated with and without arthroscopy at the time of definitive reduction and osteosynthesis.

METHODS

Retrospective cohort study. Patients with diagnosis of tibial plateau fracture Schatzker IV, V or VI who underwent reduction and definitive osteosynthesis with or without the use of arthroscopy were included. The development of compartment syndrome, deep vein thrombosis, and fracture-related infection was evaluated up to 12 months after the definitive surgery.

RESULTS

Two hundred eighty-eight patients were included: 86 with arthroscopic assistance and 202 without it. The overall complication rate in the group with and without arthroscopic assistance was 18.60% and 26.73%, respectively (P=.141). No statistical association was found between the use of arthroscopic assistance and the development of the analyzed complications.

DISCUSSION AND CONCLUSION

The use of arthroscopy to support reduction or addressing concomitant intra-articular injuries did not increase the risk of complications in patients with high-energy tibial plateau fractures at 12 months of follow up.

[Translated article] The use of arthroscopy does not increase the incidence of complications in the management of Schatzker IV-VI tibial plateau fractures

BACKGROUND AND OBJECTIVE

The use of arthroscopy for tibial plateau fractures type I, II and III according to Schatzker classification has increased, yet its employment for tibial plateau fractures Schatzker IV, V and VI is controversial due to the potential risk of compartment syndrome, deep vein thrombosis and infection. We aimed to compare the rate of operative and postoperative complications among patients with these types of tibial plateau fractures treated with and without arthroscopy at the time of definitive reduction and osteosynthesis.

METHODS

Retrospective cohort study. Patients with diagnosis of tibial plateau fracture Schatzker IV, V or VI who underwent reduction and definitive osteosynthesis with or without the use of arthroscopy were included. The development of compartment syndrome, deep vein thrombosis, and fracture-related infection was evaluated up to 12 months after the definitive surgery.

RESULTS

Two hundred eighty-eight patients were included: 86 with arthroscopic assistance and 202 without it. The overall complication rate in the group with and without arthroscopic assistance was 18.60% and 26.73%, respectively (p=.141). No statistical association was found between the use of arthroscopic assistance and the development of the analysed complications.

DISCUSSION AND CONCLUSION

The use of arthroscopy to support reduction or addressing concomitant intra-articular injuries did not increase the risk of complications in patients with high-energy tibial plateau fractures at 12 months of follow up.

A micro-CT analysis of radicular dentine thickness in mandibular first premolars presenting C-shaped root canals: Identification of potential danger zones

AIM

To describe the radicular dentine thickness in mandibular first premolars presenting C-shaped root canals, in order to identify the canal walls with less thickness as potential danger zones. In addition, to describe the internal and external anatomical characteristics of these teeth and to associate them to the dentine thickness.

METHODOLOGY

A total of 70 mandibular first premolars presenting C-shaped root canals were examined. Their internal morphology was analyzed using Vertucci´s and Fan´s criteria, and their external morphology was analyzed using the ASUDAS score. Besides, the dentine thickness around the root canals was two/three-dimensionally determined at five root planes and quantified in the distal and the mesial aspects.

RESULTS

According to Fan´s, ASUDAS, and Vertucci´s classifications, the most common canal configurations were category C3, grade 3, and type V, respectively. In Vertucci's type III anatomy, the mesial root wall of the lingual canal showed significantly less dentine thickness than the distal wall in the middle plane (p = 0.031). Similarly, in Vertucci's type V anatomy, significantly less dentine thickness was observed in the mesial root wall of the buccal and lingual canals in the middle plane (p < 0.001) and the buccal canal in the middle-apical plane (p = 0.014) than the distal root wall of these canals. In teeth with ASUDAS grade 3 and 4 scores, significantly less dentine thickness was observed in the mesial in comparison with the distal root wall of these canals. These differences were demonstrated in the middle and middle-apical planes (p < 0.001) of grade 3 teeth and the middle-apical plane (p < 0.001) of grade 4 teeth. In these root planes, the Ver1-AS3 and VerV-AS3 combinations presented a 4-times greater risk of presenting walls with a critical dentine thickness of 0.6 mm (OR=4, p = 0.025) than the combinations Ver1-AS2, VerV-AS2, VerV-AS4, and VerIII-AS3.

CONCLUSIONS

The root canal system configuration of mandibular first premolars with C-shaped canals showed a wide range of anatomical variations. The lowest dentine thickness was located in the mesial wall of the canals in the middle and apical root thirds of Vertucci´s type III and V anatomies and in teeth with deep radicular grooves scored as ASUDAS grade 3 and 4. In the middle and middle-apical planes, the presence of the combinations Ver1-AS3 and VerV-AS3 showed a high risk of presenting a critical dentine thickness of 0.6 mm. Therefore, these root canal walls with less dentine thickness represent potential instrumentation danger zones in mandibular first premolars with C-shaped canals.

The Mars 2020 Perseverance Rover Mast Camera Zoom (Mastcam-Z) Multispectral, Stereoscopic Imaging Investigation

Mastcam-Z is a multispectral, stereoscopic imaging investigation on the Mars 2020 mission's Perseverance rover. Mastcam-Z consists of a pair of focusable, 4:1 zoomable cameras that provide broadband red/green/blue and narrowband 400-1000 nm color imaging with fields of view from 25.6° × 19.2° (26 mm focal length at 283 μrad/pixel) to 6.2° × 4.6° (110 mm focal length at 67.4 μrad/pixel). The cameras can resolve (≥ 5 pixels) ∼0.7 mm features at 2 m and ∼3.3 cm features at 100 m distance. Mastcam-Z shares significant heritage with the Mastcam instruments on the Mars Science Laboratory Curiosity rover. Each Mastcam-Z camera consists of zoom, focus, and filter wheel mechanisms and a 1648 × 1214 pixel charge-coupled device detector and electronics. The two Mastcam-Z cameras are mounted with a 24.4 cm stereo baseline and 2.3° total toe-in on a camera plate ∼2 m above the surface on the rover's Remote Sensing Mast, which provides azimuth and elevation actuation. A separate digital electronics assembly inside the rover provides power, data processing and storage, and the interface to the rover computer. Primary and secondary Mastcam-Z calibration targets mounted on the rover top deck enable tactical reflectance calibration. Mastcam-Z multispectral, stereo, and panoramic images will be used to provide detailed morphology, topography, and geologic context along the rover's traverse; constrain mineralogic, photometric, and physical properties of surface materials; monitor and characterize atmospheric and astronomical phenomena; and document the rover's sample extraction and caching locations. Mastcam-Z images will also provide key engineering information to support sample selection and other rover driving and tool/instrument operations decisions.

The immune response of the scallop Argopecten purpuratus is associated with changes in the host microbiota structure and diversity

All organisms live in close association with a variety of microorganisms called microbiota. Furthermore, several studies support a fundamental role of the microbiota on the host health and homeostasis. In this context, the aim of this work was to determine the structure and diversity of the microbiota associated with the scallop Argopecten purpuratus, and to assess changes in community composition and diversity during the host immune response. To do this, adult scallops were immune challenged and sampled after 24 and 48 h. Activation of the immune response was established by transcript overexpression of several scallop immune response genes in hemocytes and gills, and confirmed by protein detection of the antimicrobial peptide big defensin in gills of Vibrio-injected scallops at 24 h post-challenge. Then, the major bacterial community profile present in individual scallops was assessed by denaturing gradient gel electrophoresis (DGGE) of 16S rDNA genes and dendrogram analyses, which indicated a clear clade differentiation of the bacterial communities noticeable at 48 h post-challenge. Finally, the microbiota structure and diversity from pools of scallops were characterized using 16S deep amplicon sequencing. The results revealed an overall modulation of the microbiota abundance and diversity according to scallop immune status, allowing for prediction of some changes in the functional potential of the microbial community. Overall, the present study showed that changes in the structure and diversity of bacterial communities associated with the scallop A. purpuratus are detected after the activation of the host immune response. Now, the relevance of microbial balance disruption in the immune capacity of the scallop remains to be elucidated.

Cascading processes in a changing environment: Disturbances on fluvial ecosystems in Chile and implications for hazard and risk management

The compound hazard effects of multiple process cascades severely affect Chilean river systems and result in a large variety of disturbances on their ecosystems and alterations of their hydromorphologic regimes leading to extreme impacts on society, environment and infrastructure. The acute, neo-tectonically pre-determined susceptibility to seismic hazards, the widespread volcanic activity, the increasing glacier retreat and the continuous exposure to forest fires clearly disturb entire riverine systems and concur to trigger severe floods hazards. With the objective to refine the understanding of such cascading processes and to prospect feasible flood risk management strategies in such a rapidly changing environment we first classify the large river basins according to a set of disturbances (i.e. volcanic eruptions, earthquakes, glacier lake outburst floods, wild fires and mass movements). Then, we describe emblematic cases of process cascades which affected specific Chilean drainage basins and resulted in high losses as tangible examples of how the cascading processes may unfold in other river basins with similar characteristics. As an attempt to enrich the debate among management authorities and academia in Chile, and elsewhere, on how to sustainably manage river systems, we: a) highlight the pivotal need to determine the possible process cascades that may profoundly alter the system and b) we suggest to refine hazard and risk assessments accordingly, accounting for the current and future exposure. We advocate, finally, for the adoption of holistic approaches promoting anticipatory adaptation which may result in resilient system responses.

[Morbimortality associated to nutritional status and feeding path in children with cerebral palsy]

INTRODUCTION

Children and adolescents with cerebral palsy (CP) have a high prevalence of malnutrition associated to poor prognosis. For an adequate nutritional assessment, new growth curves (Brooks, 2011) are available, in which precise cut-off points in Weight/Age index correlate to increased morbidity and mortality rate.

OBJECTIVE

To evaluate risk of hospitalization and death in patients with CP, according to nutritional risk (NR).

PATIENTS AND METHOD

Observational and prospective cohort study of patients with CP in an outpatient referral center. We registered demographic, socioeconomic data and nutritional assessment. During a one-year follow-up, hospitalizations and mortality were recorded. The correspondent committee extended an ethical approval.

RESULTS

81 CP patients were recruit, age 131.6 ± 60.4 months (25-313), 60 % male, 77.5 % without independent mobility. The 23 NR patients (28.4%) had lower muscle and fat mass (p = 0.000). During the follow-up, 29/81 patients required hospitalization (35.8%) and 4/81 died (4.9%). There was not an increased risk of hospitalization and/or mortality in NR group, but both were significantly higher in gastrostomy-fed children (RR: 2,98 CI 95%: 1.32-6.75 combining both variables).

CONCLUSIONS

In this study, children and adolescents with severe CP and nutritional risk had similar morbidity and mortality during a one-year follow-up, compared to those with acceptable nutritional status. Both risks were higher in gastrostomy-fed than the orally fed children.

Brentuximab vedotin plus bendamustine in relapsed or refractory Hodgkin's lymphoma: an international, multicentre, single-arm, phase 1-2 trial

Background:

The major objective of this study was to explore the safety and clinical activity of Brentuximab vedotin (Bv) and bendamustine in combination in patients with relapsed or refractory Hodgkin Lymphoma. Bv produces high response rates and durable progression-free survival (PFS) in CD30-expressing lymphomas and is approved for the treatment of relapsed Hodgkin lymphoma (HL) and relapsed ALCL. Bendamustine (B) is active agent across the lymphoproliferative malignancies, though the PFS among patients with HL and PTCL is modest.

Methods:

This was an international, multicenter, single-arm, Phase 1–2 study of BvB in patients with relapsed or refractory HL and ALCL. Eligible patients were required to have relapsed/refractory CD30+ biopsy proven HL or ALCL and an ECOG Performance Status ≤2. In the Phase 1, HL patients were deemed eligible if they developed progressive disease following or after declining ASCT, or had at least 2 prior multi-agent chemotherapy regimens. In the Phase 2, patients with HL were eligible if they had relapsed or refractory disease after one line of therapy. Eligible ALCL patients were required to have relapsed after at least one prior multi-agent chemotherapy regimen and if they were not eligible for or have declined ASCT. The primary objective of the Phase I portion of this study was to identify the maximum tolerated dose (MTD) and dose limiting toxicity (DLT). The primary endpoint of the Phase 2 portion was to determine the overall response rate (ORR; complete response [CR] plus partial response [PR])) based on an intention to treat analysis (ITT). Secondary objectives of Phase 1–2 included assessing for duration of response, progression free survival and overall survival. Response was evaluated using International Harmonization Project Group 2007 Revised Response Criteria. Bv was escalated from 1.2mg/kg Day 1, and B from 70mg/m2 Days 1 and 2 every 21 days until the MTD or recommended phase 2 dose (RP2D) was reached. The study is ongoing but no longer recruiting patients. This trial is registered with ClinicalTrials.gov number NCT01657331.

Findings:

65 patients (only 1 ALCL) were treated, 28 on the Phase 1 and 37 on the phase 2. While the MTD of the combination was not reached, the single agent MTD of Bv (1.8mg/kg Day 1) and RP2D of B (90mg/m2 Days 1 and 2) were identified as the RP2D of the combination. Patients were heavily treated, 65% (42 of 65) had an autologous or allogeneic stem cell transplant or both. The Phase 1 revealed modest toxicity. The major Grade 3/4 toxicities included Grade 3 lung infection in 5 (14%) patients in the Phase 2, and Grade 3/4 neutropenia in 13 (24%) patients across the Phase 1 and 2. The Phase 1 and 2 overall response rates (ORR) were 61% and 78% respectively, with 43% (16 of 27) patients treated in the Phase 2 attaining a complete remission (CR). In the Phase 2, the median PFS has not been reached and duration of response (DOR) was 3.4 months. There was a total of 23 deaths with 21 due to progression of disease, 2 occurring after being transplanted, and none of which were treatment related.

Interpretation:

This demonstrates that BvB might be an effective salvage regimen for patients with HL, with a favorable safety profile.

Funding:

Seattle Genetics, The Lymphoma Research Fund of Columbia University and National Center for Advancing Translational Sciences, National Institutes of Health, through Grant Number UL1TR001873 provided support for this investigator initiated sponsored trial. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.

Trehalose sustains a higher post-thaw sperm motility than sucrose in vitrified human sperm

One of the cryopreservation methods that best preserves sperm function is vitrification. However, comparative studies have not been performed to evaluate the effect of nonpermeable cryoprotectors on sperm function for prolonged periods of time post-devitrification. These times are necessary, especially in in vitro fertilisation and intrauterine insemination, for gamete interaction and then fertilisation to occur, while maintaining motility to arrive at the fertilisation site. In this study, sucrose (.25 m) and trehalose (.1 and .05 m) were compared in essential parameters like motility and plasma membrane integrity for 12 hr. Post-devitrification sperm motility using .1 m trehalose was 68.9%, higher than that obtained with .05 m trehalose (59.9%, p < .0081) and .25 m sucrose (57.9%, p < .0002). Similar results were obtained at 6 and 12 hr with .1 m trehalose (58.0% and 42.3% respectively) compared to .05 m trehalose (p < .0184 and p < .033) and .25 m sucrose (p < .0001 and p < .0012).There was no difference between .25 m sucrose and .05 m trehalose. Membrane integrity was best preserved at time 0 by .1 m trehalose (p < .05), but there was no significance at 6 and 12 hr compared to sucrose. Our results suggest that for assisted reproduction techniques that require motile spermatozoa for a longer period of time, use of .1 m trehalose is recommended in the sperm vitrification technique.

Psychometric properties of the Spanish version of the diagnostic interview for depressive personality

The aim of this study was to evaluate the reliability and validity of the Spanish-language version of the diagnostic interview for depressive personality (DIDP). The DIDP was administered to 328 consecutive outpatients and the test-retest and inter-rater reliability were assessed. Factor analysis was used in search of factors capable of explaining the scale and a cutoff point was established. The DIDP scales showed adequate Cronbach's α values and acceptable test-retest and inter-rater reliability coefficients. Convergent and discriminant validity were explored, the latter with respect to avoidant and borderline personality disorders. The results of the factor analysis were consistent with the four-factor structure of the DIDP scales. The receiver operating characteristic (ROC) analysis revealed the area under the curve to be 0.848. We found 30 to be a good cutoff point, with a sensitivity of 74.5% and a specificity of 78.5%. The DIDP proved to be a reliable and valid instrument for assessing depressive personality disorder, at least among our outpatients. The psychometric properties of the DIDP support its clinical usefulness in assessing depressive personality.

The role of glutamate signaling in pain processes and its regulation by GCP II inhibition

Glutamate is the predominant excitatory neurotransmitter used by primary afferent synapses and neurons in the spinal cord dorsal horn. Glutamate and glutamate receptors are also located in areas of the brain, spinal cord and periphery that are involved in pain sensation and transmission. Not surprisingly, glutamate receptors have been an attractive target for new pain therapies. However, their widespread distribution and array of function has often resulted in drugs targeting these sites having undesirable side-effects. This chapter will review, in general terms, the current knowledge of glutamate and its effects at various glutamate receptors with regards to nociception. In addition, we will briefly review the glutamatergic drugs currently in use as treatments for pain, as well as known novel candidates in various stages of clinical trial. Lastly, we will summarize the data supporting a novel target for pain intervention by way of GCPII inhibition, which appears devoid of the side-effects associated with direct glutamate receptor antagonists and thus holds major promise for future therapy. GCPII (glutamate carboxypeptidase II) cleaves the prevalent neuropeptide NAAG into NAA and glutamate and there is widespread evidence and belief that targeting the glutamate derived from this enzymatic action may be a promising therapeutic route.

Glutamate carboxypeptidase II in diagnosis and treatment of neurologic disorders and prostate cancer

Glutamate carboxypeptidase II (GCPII) is a membrane-bound binuclear zinc metallopeptidase with the highest expression levels found in the nervous and prostatic tissue. Throughout the nervous system, glia-bound GCPII is intimately involved in the neuron-neuron and neuron-glia signaling via the hydrolysis of N-acetylaspartylglutamate (NAAG), the most abundant mammalian peptidic neurotransmitter. The inhibition of the GCPII-controlled NAAG catabolism has been shown to attenuate neurotoxicity associated with enhanced glutamate transmission and GCPII-specific inhibitors demonstrate efficacy in multiple preclinical models including traumatic brain injury, stroke, neuropathic and inflammatory pain, amyotrophic lateral sclerosis, and schizophrenia. The second major area of pharmacological interventions targeting GCPII focuses on prostate carcinoma; GCPII expression levels are highly increased in androgen-independent and metastatic disease. Consequently, the enzyme serves as a potential target for imaging and therapy. This review offers a summary of GCPII structure, physiological functions in healthy tissues, and its association with various pathologies. The review also outlines the development of GCPII-specific small-molecule compounds and their use in preclinical and clinical settings.

Efecto de cama de pollos, subproductos de cereales y caña sobre la fisiología ruminal de ovinos

Se determinó el efecto sobre el consumo y digestibilidad aparente de niveles crecientes de cama de pollo (Cp) con harina gruesa de subproductos de maíz (Hm) o pulitura de arroz (Pa) y bagacillo de caña amonificado (40%, Ba), en raciones para corderos en crecimiento en confinamiento total. Se realizó un experimento en un arreglo factorial 2x4 en diseño de cuadrado latino con 8 corderos canulados en el rumen, incorporando Hm o Pa (48, 39, 30 y 21%, en ambos casos) y Cp (11,4; 20,4; 29,4 y 38,4%). Las raciones con Cp y Hm fueron más consumidas que las de Cp y Pa (10 a 12,1% del peso metabólico en materia seca (MS), para Hm vs. 7,6 a 9,3% para Pa) y para la materia orgánica (MO) 8,1 a 8,5% del peso metabólico para Hm y 5,8 a 6,4% para Pa; respecto a la digestibilidad aparente (DA) se obtuvo un 34,2 a 43% de la MS y 67,8 a 67,1% de la MO para raciones con Hm vs. 30,5 a 37,2% de la MS y 65,5 a 66,1% de la MO para raciones con Pa. Se apreció que el pH y el nitrógeno amoniacal, no alcanzaron los valores indicativos de acidosis ni de intoxicación con amoniaco, lo cual se correspondió con valores normales de su fisiología sanguínea para raciones con Cp y Hm. Los resultados indican que Hm y Ba en raciones con Cp permitieron un consumo y digestibilidad de los nutrientes dentro de rangos normales para corderos, sin riesgos para la salud del animal, lo cual no ocurrió con las raciones que contenían Pa y Cp.

Immunoreactive vasoactive intestinal polypeptide and vasopressin cells after a protein malnutrition diet in the suprachiasmatic nucleus of the rat

The aim of the present study was to evaluate the effects of prenatal and postnatal protein deprivation on the morphology and density of vasopressin (VP) and vasoactive intestinal polypeptide (VIP) immunoreactive neurons in the suprachiasmatic nucleus (SCN) of young rats. Female Wistar rats were fed either 6% (malnourished group) or 25% (control group) casein diet five weeks before conception, during gestation and lactation. After weaning, the pups were maintained on the same diet until sacrificed at 30 days of age. The major and minor axes, somatic area and the density of VP- and VIP-immunoreactive neurons were evaluated in the middle sections of the SCN. The present study shows that chronic protein malnutrition (ChPM) in VP neurons induces a significant decrease in number of cells (–31%,) and a significant increase in major and minor axes and somatic area (+12.2%, +21.1% and +15.0%, respectively). The VIP cells showed a significant decrease in cellular density (–41.5%) and a significant increase in minor axis (+13.5%) and somatic area (+10.1%). Our findings suggest that ChPM induces abnormalities in the density and morphology of the soma of VP and VIP neurons. These alterations may be a morphological substrate underlying circadian alterations previously observed in malnourished rats.